There is not a single task or location in the game that can't be completed without payments - it's not a matter of cash but of understanding the game and your skills. If you have any difficulties, we'd advise you to refer to other players and their experience that might be useful for you as well.
The items durability is balanced. Crafting and items earning is one of the main elements of the survival games. If the items don’t break, there will be no main gameplay. Loading time depends on your device and Internet connection.